Manufacture of magnetic records



Feb. 16, 1965 J. GROAK MANUFACTURE OF MAGNETIC RECORDS 3 Sheets-Sheet 1 Filed Oct. 5, 1959 Feb. 16, 1965 J. GROAK MANUFACTURE OF MAGNETIC RECORDS 3 Sheets-Sheet 2 Filed Oct. 5, 1959 Feb. 16, 1965 J. GROAK 3,170,044

MANUFACTURE OF MAGNETIC RECORDS Filed Oct. 5, 1959 3 Sheets-Sheet 3 D @j? Fig.5. /6I v V AMPLIFIER BANK O I l- FIG. 2is a plan view of one embodirnent of the vention,

U 'tdStt Pt 111 i Patented Feb. 16, 1965 V 7 FIG. 3 is a side. elevation of the apparatus shown in FIG. 2, M Niggiggfiggfigg l igg j g fifigcfigg s a section on the line IVIV of FIG. 2,

H I Landon NW 4Eugland 2 1s a schematic view Or a second embodlment Fiied Uct.5,1959,Ser.No.844,493 5 01 h 1 1 Claims priority, application Great Britain, Oct. 15, 1958, 6 1s a View In the dlrectlon of theiarrow VI 111 32,969/58 FIG. 5, and i p 12 Claims. (Cl. 179-49052) FIG. 7 is a'sketch illustrating a third embodiment ofi 3 the invention. a 1';

The present invention relatesto the production of mag- 10 The apparatus shown in FIGS. 2 to 4 comprises two netic records, that is records in'which informationv is reangle irons 14 fixed to a main bed 15. One flange of each corded as a magnetis'ed track on a flexible sheet of magne angle iron is vertical and parallel to'the vertical flange tisable material. The invention is concerned with records of the other angle iron, a channel for a carriage'12 being of the type having a number of parallel tracks and records formed between the vertical flanges. Parallel rails 13 in the form of a sleeve having a helical track, which may 15 lie at the bdttom of'the channel. .The' other flanges of be regarded as a number of parallel tracks. The recorded the angle irons are horizontal and extend outwardly of. information may be recorded sound such asfspeech or the channel, being covered withsheets 1t) and 11 of nonmusic, but is not necessarily such. magnetic material forming'beds for strips of:film ma- It is an object of the invention to provide an improved 5 terial. A master strip 16 (such as is shown in FIG. 1 method whereby a large number of records can be profor example) is fixed to-the bed It), being held by a clamp; duced'froma'master record in ajrelatively short time. Y ing plate 17 at one end and bystrip-tensioning means 18 According to the invention there is provideda method at the other end. The master {strip l'bears fiveparallel of manufacturing a magnetic record wherein a plurality of recorded tracks of magnetic material and his required secti'o11s""of.a master recordare' scanned togetherin one to reproduce the record by recordingon to'a strip of film movement by a corresponding plurality of reproducing l9'held on the bed 11. This is effected by way of the heads, andithe outputs of the reproducing heads are applied carriage'lzf. a i V to a corresponding plurality of recording heads co-oper- The carriage has a main frame 20.in--which are jourating with a magnetic recording medium, there being 'relanailed the spindles of three grooved Wheels 21, 22 and tive motionbetweenthe recording heads and the magnetic ,23'. The'wheel 21 is on one side of the carriage and runs recording medium whereby a record is producedin which pn onerail 13, the wheels ,22 and 23 being in-alignment information 'is recorded along 'a plurality of, parallel on the other side of the carriage and running on the other tracks. 3 Y rants;

v The invention also relates to apparatus for carrying I V A block 24is fixed on top of the main frame i2 and o'n out the methodf. y l each side of the block there are two transversely projectt Thej recordingrriedium-may be either an' open-endeld ingarms"ZSflOnlythe structure borne by the arms 25; sheet or a sleeve. A'n openeende'd sheet maybe joined onthef'master stripside'of the carriage will be described, g to'torm a sleeve-ndirl particularmay be'joined with a in" detail as the structure on the. other. side' is exactly, staggeredjoint so that,,,tracksrecorded-parallel to the" complementary, I edges of the sheet 'join toform a helicaltrack. C Onearm Z5 "bears an arm 26 extending lengthwise of' The methodniaybe carried out conveniently when'the: (it) the bed and capable otpivotal upanddown movement recording medium is an 'ope n-e'nded sheet by placing the {1;}. on the fre'efend-of the arm 26is a'brassblock 27 which Street on a ilat bed, pins'or'other means beingprovided extends over the'width of the master strip 16 andhas to effectfregistration, and moving 'the recording heads three magnetic reproducing heads 28 alignedrespectively over thef'sheet in a carriage; With this'arrangernent feedwith' theutwo outer ones and the middle one "of the fivei 7 ing mechanism such a'sj'that employed in the printingvintracks on the stripfl'6. A light spring 29supported on a dustry maybe employed to .feed sheets of recording; bracketfitl fixed toztheblock 24bears on the arm 26 and; medium on to theabed between successive recording trai hencejholds the heads 28' against the strip 16 In like verses of the carriage. This enables the method to be wayan'arm' 31 on the other rod 25 bears a block 32 havcarried put automatically'at high'speed. ing'yhe ads '33 aligned with the other two tracks on the The master record is preferably likewise'e'itheran open-150 stri'p16. The staggering of thethree heads 28 with reended sh eetior a sleeve with parallel tracksjherleon but spect to the two heads 33 is done in order to be able to may consist'of a number of lengthsof magnetic tape fed align heads with'each, of the closely spaced tracks on the 'p'ast 'the individual recording heads at the same time. 7 In strip 16. j r j a the latter 'casehowever problems. of synchronism are Flexible wires (not shown) are takenfromthe heads 28 greater. V r

a l and33 to a bank of five amplifiers (not shown) which For scanning the tracks of the master record either supply's'ignals, again through flexible wires tofive'record-j the record or. the reproducingfhead's may be moved, inghead's 34 aligned with five tracks of magnetic record? Similarly either the recordingmedium orjthe recording, ingmaterialon the strip 19. v I h heads maybe moved v As the carriage 12 is movedalong therails 13'signals The two pluralities of heads are preferably in the form are picked up' simultaneously fromthefive tracks of the 'oftwo, multitrack heads. For closely spaced tracks it master strip 16, are amplified and are'recorded simulmay be necessary to stagger adjacent heads. It willbe taneously on then-e tracks of the strip 19. Thus areplica appreciated that individual amplifiers can jbe provided in of 'themaster strip'is made. Since all heads move on the the channels connecting thefrecor'ding heads to the repr O- "same carriage absolute synchronism'is achieved, the stagducing heads. 7 5 I geringiofthe heads beingimmaterial so far=as this is con- 7 .The invention will'now bedescribed by "way off-ex V 'cern'edf j t V ample with reference to the accompanyingdrawingslin The carriage is driven backwards and forwards by which: Y a p means of a cord 35, which having both ends fixed to the FIG. '1' showspart ofv a magnetic record such as may mainframe 2h of the carri'agelZ, forms an endless loop. be reproduced 'by the 'methodzof the invention, One end of the loop.passes-roundatreelyrotatable pulley 36 and theother [round a driven pulley 37, the run be: .1

tween pas'sing through an aperture 38 in the .frame 20.

' Bataan -of the carriage in the other direction.

3 The pulley 37 is fixed to a shaft 39 which also bears a flywheel 46 Drive is imparted to the flywheel by a capstan 41 driven by a motor 42 through an idler 43 mounted on a swinging arm 44 and biased by a spring 45 between the capstan 41 and the edge of the flywheel 40.

The bed for supporting the recording material may be provided with associated feed mechanism for feeding sheets of material on to the bed and removing recorded sheets therefrom. Automatic operation of this mechanism and the carriage can be controlled by means of microswitches engaged by the carriage at the end of each traverse. Thus it is arranged that there is a dwell pe riod of the carriage at the end of each traverse during which the feed mechanism operates. A record is made during all traverses in either direction.

Alternatively there may be substantially no dwell period, recording being effected only during traverses in one tion can also be compounded of motion of both theheads and the cylinder. a

One arrangement isshown in FIG. 7 and comprises a drum 76 mounted on a spindle 71 and, in operation, driven round slowly on that spindle. The drum is encircled by a master record 72 and a strip of recording material 73. A set- 74 of reproducing headsco-operate with five tracks on the record 72 and leads 75 go from the reproducing heads toamplifiers (not shown). Leads 76 from the amplifiers go to a set of recording heads77" co-operating with five tracks on the strip 73.

V The apparatus shown FIGS-5 and 6 comprises oneflat,

bed with associated feed mechanism (not shown) for the recording .material 51. A carriageSZ with recording heads 53 has wheels 54 running on rails 55 over this bed and is driven along the rails by means of a synchronous electric motor 56 operatinga precision capstan 57 against one of the rails 55.

The recording heads 53 are connected by a flexible cable 58 through amplifiers 59 to a. set of fixed reproducing heads 60. The master record is in the form 'of a sleeve 61 driven round 'on two drums 62 continuously (between C and D) run in the opposite direction. and are utilised to provide signals for recording during traverses.

The feed mecha loop and hence high rates of production can be achieved. Likewise, in the apparatus first described, the carriage may carry several sets of recording heads coupled to the one set of reproducing heads.

The recording material can be coated overall with magnetic material for producing long-playing sound records. The material may also be film-base material coated only along strips with spaces between for lines of pictures, as shown in FIG. 1. Here 35 mm. film is provided with five tracks 84 of pictures between'the customary sprocket punchings 81. Interleaved with the five tracks 80 are five magnetic tracks 82. The strip is also provided with a pattern of punchings 83 used in driving the film in reproducing apparatus by means of pinned rollers. Furthermore the material may be opaque film-base material, pictures for reproduction by means of reflected light being printed on one side and the other side coated with magnetic material on which an associated sound track is recorded.

I claim:

1. Apparatus for rapidly making a duplicate of a magnetic record having a continuous record of information divided into a plurality of parallel arranged component tracks presenting said information in sequence through said tracks comprising scanning means for scanning said tracks simultaneously, said scanning means comprising a plurality of transducer heads cooperating with said component tracks respectively, a second like plurality of transducer heads, coupling means for applying signals developed by the first said transducer heads to the second said transducer heads respectively and means for moving said second transducer heads and magnetic recording medium relative to one another so that said second transducer heads lay down parallel magnetic tracks corresponding to and duplicating said component tracks of the first said magnetic record respectively.

, 2. A method of rapidly duplicating a magnetic record of information comprising the steps of: providing an endless loop of material having a plurality of helically' parallel tracks of information recorded thereon, the end of each track being jonied to the beginning of asuccessive track to form a continuous helical track of information on said loop; scanning each of said tracks with a like plurality of scanning means; and recording a like plurality of helically parallel tracks on a second endless-loop.

' tinuous helical track; cutting said endless. loop transnism operates whilstthe spacing section(between B and C and D and A) pass the reproducing heads 60.

The carriage motor 56, which should be of high starting torque, and the feed mechanism are controlled by signals derived from the master record. This may be done by stops on the recordactuating trips, photoelectrically or, as shown, by means of a separate magnetic track and sults if the carriage has only to travel backwards and forwards say three feet.' A convenient size of film record need only be of tthis' length.

It will beappreciated'that more than one carriage with its set of heads can be controlled from the one master the motion of the-car- 2 parallel trackson a second flat sheet.

'Versely forming a flat sheet having said single helical track now divided into -a plurality of parallel tracks; scanning said llflfOIIl'lZtilOIl OIl each of said parallel tracks; and recordmg saicl scanned information in a like plurality of 4. A method of rapidly duplicating a magnetic record of informationcomprising the steps of: providing an endless loophaving information recorded thereon in a con: tinuous helical track; cutting said endless loop transversely forming a flat sheet'having said single helical track now divided into a plurality of parallel tracks; scanning said information on each. of said parallel tracks; recording said scanned information in a like plurality of parallel tracks on a second flat sheet; and joining the ends of said u, second flat sheet to form a second endless loop having said parallel tracks matched to form a continuous helical track of recorded information. v i V 5. Amethod of rapidly duplicating a magnetic record of information comprising the steps of: providing an endless loop having information recorded' thereon in a continuous helical track; cutting said endless loop transversely forming a fiat sheet having said single helical track now divided into a plurality of parallel tracks; scanning said information on each of'said parallel tracks at substantially the same time; and recording said scanned information in a like plurality of parallel tracks on a second llat sheet.

6. A method of rapidly duplicating a magnetic record of information comprising the steps of: providing an endless loop having information recorded thereon in a continuous helical track; cutting said endless loop transversely forming a flat sheet having said single helical track now divided into a plurality of parallel tracks; scanning said information on each of said parallel tracks at substantially the same time; and recording said scanned information in a like plurality of parallel tracks at substantially the same time on a second fiat sheet.

7. A method of rapidly duplicating a magnetic record of information comprising the steps of: providing a first sheet of material having recorded thereon a plurality of parallel tracks of information in a sequence such that when the ends of said first sheet are joined the end of each track coincides with the beginning of a successive track to provide a continuous helical track of information; scanning each of said plurality of tracks with a like plurality of scanning means to obtain data therefrom; and recording said data on a like plurality of parallel tracks on a second sheet of material.

8. A method of rapidly duplicating a magnetic record of information comprising the steps of: providing a first sheet of material having recorded thereon a plurality of parallel tracks of information in a sequence such that when the ends of said first sheet are joined the end of each track coincides with the beginning of a successive track to provide a continuous helical track of information; scanning each of said plurality of tracks substantially simultaneously with a like plurality of scanning means to obtain data therefrom; and recording said data as it is scanned on a like plurality of parallel tracks on a second sheet of material. 7

9. Apparatus for rapidly making a duplicate of a magnetic record having a continuous record of information divided into a plurality of parallel arranged component tracks presenting said information in sequence through said tracks comprising, in combination, two parallel beds for supporting the magnetic record and a magnetic recording medium, respectively, a carriage movable parallel to said beds, first and second sets of transducer heads carried by the carriage, said carriage supporting the first transducer heads in spaced apart relationship across the Width of one bed for cooperation with the magnetic record thereon and supporting the second transducer heads in spaced apart relationship across the width of the other bed for cooperation with the magnetic recording medium thereon, a plurality of amplifiers each having an input and an output, leads connecting said first transducer heads to the inputs, respectively, of said amplifiers, further leads connecting said outputs of said amplifiers to said second transducer heads, respectively, and motor means for so driving said carriage backwards and for- Wards that said first transducer heads scan said magnetic record and said second transducer heads lay down parallel magnetic tracks corresponding to andduplicating said component tracks of the magnetic record.

10. Apparatus for rapidly making a duplicate of a mag netic record having a continuous record of information divided into a plurality of parallel arranged component tracks presenting said information'in sequence through said track-s comprising, in combination, rotatable means 6 for supporting said magnetic record in a loop and for moving said magnetic record around a looped path, a first set of transducer heads disposed in fixed position across said path for cooperation with said magnetic record, a linear bed for supporting a magnetic recording medium, a carriage movable parallel to said bed, a second set of transducer heads carried by the carriage in spaced apart relationship across the Width of the bed for cooperation with said recording medium, a plurality of amplifiers each having an input and an output, leads connecting said first transducer heads to the inputs, respectively, of said amplifiers, further leads connecting said outputs of said amplifiers to said second transducer heads, respectively, and

- motor means for so driving said loop around said looped path and for so driving said carriage backwards and for- Wards that said first transducer heads scan said magnetic record and said second transducer heads lay down parallel magnetic tracks corresponding to and duplicating said component tracks of the magnetic record.

11. Apparatus for rapidly making a duplicate of a magnetic record having a continuous record of information divided into a plurality of parallel arranged component tracks presenting said information in sequence through said tracks comprising scanning means for scanning said tracks simultaneously, said scanning means comprising a plurality of transducer heads cooperating with said component tracks respectively, a second like plurality of transducer heads, coupling means for applying signals developed by the first said transducer heads to the second said transducer heads respectively, means for moving said second transducer heads and magnetic recording medium relative to one another so that said second transducer heads lay down parallel magnetic tracks corresponding to and duplicating said component tracks of the first said magnetic record respectively, and means responsive to cueing signals developed from said magnetic record to control the automatic operation of said apparatus.

12. A method of rapidly duplicating a magnetic record of information comprising the steps of: providing an endless loop having information recorded thereon in a continuous helical track; cutting said endless loop transversely forming a first flat sheet having said single helical track row divided into a plurality of parallel tracks; placing said first fiat sheet and a second fiat sheet on parallel beds, respectively; and moving a carriage carrying means for scanning said first sheet and means for recording on said second sheet along said beds to effect scanning said information on each of said parallel tracks and recording said scanned information in a like plurality of parallel tracks on said second fiat sheet at substantially the same time.

References Cited in the file of this patent UNITED STATES PATENTS 

10. APPARATUS FOR RAPIDLY MAKING A DUPLICATE OF A MAGNECTIC RECORD HAVING A CONTINUOUS RECORD OF INFORMATION DIVIDED INTO A PLURALITY OF PARALLEL ARRANGED COMPONENT TRACKS PRESENTING SAID INFORMATION IN SEQUENCE THROUGH SAID TRACKS COMPRISING, IN COMBINATION, ROTATBLE MEANS FOR SUPPORTING SAID MAGNETIC RECORD IN A LOOP AND FOR MOVING SAID MAGNETIC RECORD AROUND A LOOP PATH, A FIRST SET OF TRANSDUCER HEADS DISPOSED IN FIXED POSITION ACROSS SAID PATH FOR COOPERATION WITH SAID MAGNETIC RECORD, A LINEAR BED FOR SUPPORTING A MAGNETIC RECORDING MEDIUM, A CARRIAGE MOVABLE PARALLEL TO SAID BED, A SECOND SET OF TRANSDUCER HEADS CARRIED BY THE CARRIAGE IN SPACED APART RELATIONSHIP ACROSS THE WIDTH OF THE BED OF COOPERATION WITH SAID RECORDING MEDIUM, A PLURALITY OF AMPLIFIERS EACH HAVING AN INPUT AND AN OUTPUT, LEADS CONNECTING SAID FIRST TRANSDUCER HEADS TO THE INPUTS, RESPECTIVELY, OF SAID AMPLIFIERS, FURTHER LEADS CONNECTING SAID OUTPUTS OF SAID AMPLIFIERS TO SAID SECOND TRANSDUCER HEADS, RESPECTIVELY, AND MOTOR MEANS FOR SO DRIVING SAID LOOP AROUND SAID LOOPED PATHS AND FOR SO DRIVING SAID CARRIAGE BACKWARDS AND FORWARDS THAT SAID FIRST TRANSDUCER HEADS SCAN SAID MAGNETIC RECORD AND SAID SECOND TRANSDUCER HEADS LAY DOWN PARALLEL MAGNETIC TRACKS CORRESPONDING TO AND DUPLICATING SAID COMPONENT TRACKS OF THE MAGNETIC RECORD. 